Unexpected - Stalin fires HE when AP available

[PoorOldSpike]

It was my panzer on the receiving end, here the HE round simply splatters against the front of my boy without hurting the tank or crew.
PS - and a second later he fires back on the move at the Stalin (inset,a miss), how kool is that?
Incidentally notice the Stalins HE shell hit the paper-thin turret front, confirming just how poor HE is against armour..